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111.
Waldo C. Ault Margaret L. Swain Lawrence C. Curtis 《Journal of the American Oil Chemists' Society》1947,24(9):289-290
Summary The seeds and the oil from the seeds of two perennial gourds,Cucurbita palmata andCucurbita digitata, which grow wild in the Southwestern States, have been examined. Approximately two-thirds, by weight, of the whole dried
fruit is seeds. The seeds contain about 28–30% oil and somewhat higher percentages of protein. The oils from both species
are chiefly characterized by 10.0 to 17.0% of a conjugated trienoic acid similar to the eleostearic acid of tung oil, but
apparently not identical with it.
Analytical data are shown pertaining to the whole seeds as well as the oil extracted from them.
Presented at the 38th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., May 20–22, 1947.
One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S.
Department of Agriculture. 相似文献
112.
Fracture toughness behavior, stress–strain behavior, and flaw resistance of pressureless-sintered Si3 N4 -BN ceramics are investigated. The results are discussed with respect to the reported thermal shock behavior of these composites. Although the materials behave linear-elastic and exhibit no R -curve behavior, their flaw resistance is different from that of other linear-elastic materials. Whereas the critical thermal shock temperature difference (Δ T c ) is enhanced by adding BN, the content of BN has no influence on the strength loss during severe thermal shocks. 相似文献
113.
YJ Woo GP Raju JL Swain ME Richmond TJ Gardner RJ Balice-Gordon 《Canadian Metallurgical Quarterly》1997,96(10):3561-3569
BACKGROUND: The relationship among the maternal, placental, and uniquely shunted embryonic circulation was explored to provide access to the embryonic cardiovascular system in utero. Manipulation of gene expression in the developing heart would be particularly useful for studying the effects of altered gene expression on cardiac development and in the etiology of congenital cardiac anomalies. METHODS AND RESULTS: Dye studies demonstrated that intraplacental injection allows direct access to the embryonic cardiac and systemic circulation. To evaluate the efficacy of cardiac gene transfer using this approach, replication-deficient recombinant adenoviral vectors encoding luciferase or beta-galactosidase as reporter genes were injected intraplacentally into embryonic day (E)12.5 murine embryos, an age at which the mass of the heart was observed to be large compared with other organs. Embryos were assayed for transgene expression at E15.5 and at birth. Survival rates at these times were similar among vector-injected and control groups. At E15.5 and at birth, luciferase activity within the heart was 9- and 23-fold higher, respectively, than in the remainder of the embryo, although levels of expression were generally lower at birth than during embryonic life. Beta-galactosidase expression was observed within all regions of the embryonic heart and was localized to approximately 15% of atrial and ventricular cells. CONCLUSIONS: Intraplacental delivery of adenovirus at embryonic day 12.5 results in somatic gene transfer to the murine embryonic heart, which persists at least until birth. The combination of intraplacental injection to directly access the fetal coronary circulation and injection at E12.5 when the mass of the heart is large compared with other organs results in transgene expression in cardiac cells. Intraplacental injections early in embryonic life may thus be useful to study the effects of temporal manipulation of gene expression on cardiac development and disease. 相似文献
114.
Shisslak Catherine M.; Crago Marjorie; Neal Mary E.; Swain Barbara 《Canadian Metallurgical Quarterly》1987,55(5):660
Eating disorders have increased dramatically over the past two decades, but the primary prevention of these disorders has received little attention. This article summarizes our current understanding of anorexia nervosa and bulimia and offers some suggestions for the primary prevention of these disorders at the individual, family, and community levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Shisslak Catherine M.; Crago Marjorie; Schnaps Laura; Swain Barbara 《Canadian Metallurgical Quarterly》1986,23(4):598
Describes interactional group therapy for anorexic and bulimic women, as it was used for 12 groups (with 4–8 Ss each) conducted over 4.5 yrs. Bulimics and anorexics were combined because it is believed that the 2 types of eating-disordered patients have much that they can learn from each other. Group themes particularly relevant to eating-disordered women are discussed, including confidentiality, sexuality, commonalities between the 2 types, and transference. Stages in the evolution of the group and strategies for facilitating group process are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
117.
Based on single residue substitutions, previous studies suggested that Gln165, His197, and His265 of the neurokinin-1 receptor interact directly with many nonpeptide antagonists, including CP-96,345. To further test this model, all three residues have been substituted simultaneously with alanine. The Q165A-H197A-H265A triple mutant bound CP-96,345 and eight analogs with similar affinity (2-20 microM), even though the same series of compounds bound to the wild-type receptor with affinities over a range of 1000-fold. These observations correspond exactly to the prediction of the binding site model. The micromolar binding affinity of all tested CP-96,345 analogs for the triple mutant seems to reflect solely van der Waals interactions, which suggests a significant contribution of conformational compatibility (or shape complementarity) to binding affinity. The primary role of conformational compatibility in ligand binding was consistent with the observation that simply transferring the residues involved in polar interactions with beta2-agonists into the neurokinin-1 receptor did not lead to increased binding affinity for the beta2-agonists. Taken together, these results support a general principle of ligand-receptor binding in which specific polar interactions can take place only if the overall ligand conformation is compatible with the stereochemistry of the binding pocket. In addition, double-residue and triple-residue substitutions, in combination with single-residue substitutions, can provide an alternative route to reveal multiple interactions that may not be detectable by single-residue substitutions and represent a novel approach to examine ligand-receptor interactions in the absence of high-resolution structural data. 相似文献
118.
G. A. Gogotsi V. P. Zavada M. V. Swain 《Journal of the European Ceramic Society》1995,15(12):1185-1192
Investigations were carried out on four tetragonal zirconia polycrystalline (TZP) ceramics of differing grain size containing 9 mol% CeO2. Precision flexural tests on these materials were conducted to determine the elastic modulus, the non-linear deflection and the associated acoustic emission during such testing. The deformation was characterized in terms of the number and size of the transformation bands that developed during the non-linear response. The finest grained material initially exhibited permanent set without the presence of such bands, whereas all the coarser grained materials showed a linear relationship between the summation of the band widths and the residual deflection. The acoustic emission and plastic strain behaviour are discussed in terms of the number and size of the stress induced phase transformation bands. 相似文献
119.
The paper presents a new approach for the estimation of harmonic components of a power system using a linear adaptive neuron called Adaline. The learning parameters in the proposed neural estimation algorithm are adjusted to force the error between the actual and desired outputs to satisfy a stable difference error equation. The estimator tracks the Fourier coefficients of the signal data corrupted with noise and decaying DC components very accurately. Adaptive tracking of harmonic components of a power system can easily be done using this algorithm. Several numerical tests have been conducted for the adaptive estimation of harmonic components of power system signals mixed with noise and decaying DC components 相似文献
120.
Michael V. Swain Richard H. J. Hannink 《Journal of the American Ceramic Society》1989,72(8):1358-1364
Observations of the grinding-induced transformation in singlephase Ce-TZP materials, referred to in an earlier paper, are presented. Two techniques were used to grind the surface: by hand in a slurry of abrasive particles and with a high-speed diamond-impregnated wheel. Significant differences in X-ray diffraction profiles between the two grinding methods was observed. Limited monoclinic ZrO2 was detected on the machineground surface, along with the reversal of the tetragonal ZrO2 (200) peak intensities. On the hand-ground surface, considerable monoclinic phase was observed. The disappearance of the monoclinic phase with heating was followed by X-ray diffraction, and the A f was found to exceed 700°C, while the reversal in tetragonal (200) peak symmetry and intensity remained unaltered up to at least 1000°C. Transmission electron microscope studies at various depths below the ground surface were undertaken to identify the differences between these surfaces and fractured surfaces. A simple explanation is proposed for the reversal of the tetragonal peak intensities. This reversal has previously led to the notion of a ferroelastic toughening mechanism in similar TZP materials. 相似文献